UK pig farmers are being warned to be on the alert following an “extremely concerning” outbreak of African swine fever (ASF) in wild boar in Belgium.

Pigs after infection with virulent African swine fever virus. They have very high temperatures (over 41C), are lethargic, do not want to move, and lose their appetite, and there is conjunctivitis and reddening of the ears Picture: THE PIRBRIGHT INSTITUTE

East Anglian pig consultant Peter Crichton described it as “shattering news”.

Pig farmers’ levy payers’ body, the Agriculture and Horticulture Development Board (AHDB), warned the deadly notifiable disease for pigs, which does not affect humans, is highly contagious.

“It is extremely concerning that African swine fever (ASF), a virus that affects pigs and wild boar, has been identified in Belgium. Focus must be on ensuring ASF does not spread further,” AHDB said. “We urge all pig producers to ensure their biosecurity is tight, particularly vehicles, animals and people coming onto their units. We need all pig producers, farmers and the public to pull together to keep this disease out.

“African swine fever (ASF) is a highly contagious disease of pigs, warthogs, European wild boar and American wild pigs. It does not affect humans.”

Symptoms include fever, loss of appetite lack of energy sudden death with few signs beforehand, as well as vomiting, diarrhoea, and red or dark skin. Mortality rates can be as high as 100%.

Mr Crichton, who is based at Bury St Edmunds, said measures were already in place to prevent the possible spread of the disease in non-wild boar which could then be transmitted to pig farms.

“It is hoped that these latest outbreaks will not jeopardise the ability of the European Union to continue to export pig meat to China,” he said.

The Department for Environment, Food and Rural Affairs (DEFRA), which is monitoring the situation, said the outbreak concerned four wild boar in the Luxembourg region, close to the border with France.

The most likely mode of transmission is from infected meat products from infected areas being brought into the area by humans, it said.

Anyone who you suspects the presence of the disease must report it immediately by calling the Department for Environment, Food and Rural Affairs (DEFRA) Rural Services Helpline on 03000 200 301. Failure to do so is an offence.